I have (or should I say "had") two worm bins in my garage. However, the first bin I made must not have made the worms happy, because they kept escaping and I would find them lined up around the top whenever I'd open the bin. The top also had an excess amount of moisture around it, which I think was the problem. For that bin, I used the instructions on YouTube from Garden Girl.
The second bin, I didn't bother to put cardboard in the bottom, but instead went through my outside compost pile (we have a large pile out back that we've had going for a number of years, though not with the intention of having composting worms - that just happened on its own) collecting worms and adding them to the bin, along with some of the compost they were in. I then added a layer of leaves and topped it off with a bit of shredded newspaper that I dampened slightly with water. I have since added 100 worms to each bin (I purchased 4 containers of Red Wigglers at
PetSmart), and the worms in the second bin appear very happy (no prison breaks, as my son likes to call them).
Anyway, I went out tonight to feed the second bin and decided to check on the first. Once again, I found several worms around the top and a LOT of condensation. I then moved the bin and found several more worms underneath, so I decided that enough was enough and just combined bin #1 and bin #2 into bin #2. I just went out and peeked, and it appears - for now - that things are settling down.
Let me add that I only started these bins a couple weeks ago and I'm already seeing a lot of castings and quite a few baby worms. I figure I'll get things straightened out eventually and all my worms can live happily in their bins (I do plan to start over on bin #1 by dividing half of bin #2 back into bin #1, and will just make sure it isn't nearly as wet this time). I think it's just a matter of finding the right balance - not too wet, not too dry, etc. If all else fails, my bin worms will be released "into the wild" in my compost pile out back!